60 lines
1.7 KiB
C
60 lines
1.7 KiB
C
|
/* $OpenBSD: getentropy_win.c,v 1.5 2016/08/07 03:27:21 tb Exp $ */
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Copyright (c) 2014, Theo de Raadt <deraadt@openbsd.org>
|
||
|
|
* Copyright (c) 2014, Bob Beck <beck@obtuse.com>
|
||
|
|
*
|
||
|
|
* Permission to use, copy, modify, and distribute this software for any
|
||
|
|
* purpose with or without fee is hereby granted, provided that the above
|
||
|
|
* copyright notice and this permission notice appear in all copies.
|
||
|
|
*
|
||
|
|
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
|
||
|
|
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
|
||
|
|
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
|
||
|
|
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
|
||
|
|
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
|
||
|
|
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
|
||
|
|
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
|
||
|
|
*
|
||
|
|
* Emulation of getentropy(2) as documented at:
|
||
|
|
* http://man.openbsd.org/getentropy.2
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include <windows.h>
|
||
|
|
#include <errno.h>
|
||
|
|
#include <stdint.h>
|
||
|
|
#include <sys/types.h>
|
||
|
|
#include <wincrypt.h>
|
||
|
|
#include <process.h>
|
||
|
|
|
||
|
|
int getentropy(void *buf, size_t len);
|
||
|
|
|
||
|
|
/*
|
||
|
|
* On Windows, CryptGenRandom is supposed to be a well-seeded
|
||
|
|
* cryptographically strong random number generator.
|
||
|
|
*/
|
||
|
|
int
|
||
|
|
getentropy(void *buf, size_t len)
|
||
|
|
{
|
||
|
|
HCRYPTPROV provider;
|
||
|
|
|
||
|
|
if (len > 256) {
|
||
|
|
errno = EIO;
|
||
|
|
return (-1);
|
||
|
|
}
|
||
|
|
|
||
|
|
if (CryptAcquireContext(&provider, NULL, NULL, PROV_RSA_FULL,
|
||
|
|
CRYPT_VERIFYCONTEXT) == 0)
|
||
|
|
goto fail;
|
||
|
|
if (CryptGenRandom(provider, len, buf) == 0) {
|
||
|
|
CryptReleaseContext(provider, 0);
|
||
|
|
goto fail;
|
||
|
|
}
|
||
|
|
CryptReleaseContext(provider, 0);
|
||
|
|
return (0);
|
||
|
|
|
||
|
|
fail:
|
||
|
|
errno = EIO;
|
||
|
|
return (-1);
|
||
|
|
}
|